Centre of Food Physics
The competitiveness of the food industry is governed by the question of how much the food products comply with the consumer’s needs. One of the keys to success - apart from the effective production of traditional products - is the development of new products. No matter which approach is chosen, there is only one thing that is important: changing the structure of the raw materials in such a way as to produce the desired food products’ properties.
Based on thorough research, the Centre of Food Physics (ZLP) has assumed the task of unveiling the relationship between structure and function and to gather knowledge about the structure forming mechanisms in system engineering processes. The scale-up of technical and industrial applications is conducted in close cooperation with the other divisions of the DIL (German Institute of Food Technologies). In this way, we are able to handle complete R&D projects for our customers efficiently and on a high level.
Dr.-Ing. habil. Ute Bindrich
Manager Division Centre of Food Physics
Structure Analysis
Almost all processing or quality relevant properties are defined by structure. Even if the chemical composition is identical, different structures may change the properties of a product dramatically. The ZPL applies suitable examination methods and advanced instruments to characterize structures even in the nanometer range qualitatively and in parts also quantitatively. The characterization of boundary layer networks is of specific significance because these are often decisive for the rheological properties and the texture of a product. In this case, the structure is depicted using a combination of image processing methods and statistical evaluation.
Thermal analysis
Thermal analysis is used for the description of processes that are characterized by a pick-up or release of heat, including:
- melting and solidification processes
- crystallization into different crystal modifications
- dissolution processes
Added to that, the specific heat capacity of substances can be determined. Mechanical stability and mouthfeel of fat-containing material systems are dependent on the melting properties of the fats. These however are not
only influenced by the type of fat and its triglyceride spectrum but also by its crystal structure as most fats follow a polymorphic crystallization pattern.
Rheology
The determination of rheological properties including flow behavior, elasticity, plasticity, visco-elasticity, yield strength and breaking point is significant for the characterization of the quality and processing properties of material systems (design of pumps, pipelines, processing temperature, etc) and with that for the properties of substances. However, adjusting the measurement conditions to the precise problem is key. Most important is the temperature at which the rheological parameters are taken. The ZLP can measure a broad temperature range, for example, ice cream at -15 °C and melting properties at +150°C.
Tensiometry
Each system strives for minimum enthalpy (second law of thermodynamics). If substances of different polarity are mixed, a surface tension develops in the contact area. This results in a complete separation of the phases as long as there are no amphiphilic substances (emulsifiers) present, which reduce the surface tension sufficiently. The ZLP is able to illustrate the relationship at equilibrium (static state) and at different surface ages (dynamical state) qualitatively and quantitatively for a temperature range between 5 °C and 75 °C. However, it is not just fluid systems that are subjected to the examinations; the characterization of the surface energy of powders as a sum of the polar and disperse fractions provides valuable insight into the wetting behavior of powders in hydrophilic and hydrophobic environments.
Particle Measurement
The properties of disperse systems are influenced by the particles they contain. The most important parameters are the size (distribution), charge, polarity, density, porosity and surface topography. Depending on the shape of the particles, either a laser diffraction spectrometer (for almost spherical particles in the range between 20 nm and 2,000 ?m) or a microscope with subsequent image analysis is used for the determination of the particle size distribution in disperse systems and powders. The traditional sieve analysis is also part of our service range. If the disperse phase consists of particles at different states of aggregation, the particles are separated prior to the measurement and the phases are assessed with different methods.
Highly qualified and experienced personnel are available for the above described tasks. They will solve problems quickly and reliably. The service range will continually expand by applying newly developed methods and
techniques.
Links
www.asylumresearch.comwww.atomicforce.de
Our Service Catalogue is available here.
For further information about the activities of the centre of food physics, 
please download our brochure here.
